Group 1 of 1560 sardinians from the Lanusei Valley were included in the study.
The Italian group had a mean age of 42.7 with a range from 14 to 94.
The study on the human subjects was approved by the Institutional review boards in Italy and the USA.

Group 2 of 1131 community-dwelling Americans were included in the study.
The American group had a mean age of 57.3 with a range from 20 to 93.
The study on the human subjects was approved by the Local institutional review board.